Calculates the predicted y-value for a linear regression.
Syntax:
FORECAST( x:Number, y‑data:Range or Array, x‑data:Range or Array )
Returns the predicted y-value corresponding to the given x-value using the linear regression line given by the y‑data and x‑data arrays.
Note:
FORECAST()
is implemented using a two-pass approach, first independently computing the mean values,
then computing intermediate values (such as the sum of the squares, products) using the difference between each value and the corresponding mean value.
This approach helps avoid many round-off errors and is also employed by Microsoft Excel 2003 and later.
Revisions:
This function was added in Fireworkz 2.00.